Shock absorber



C. H. FOSTER April 11, 1933.

SHOCK ABSORBER Filed June 7, 1929 3 Sheets-Sheet l April 11, 1 933. c. H. FOSTER 1,903,447

SHOCK ABSORBER Filed June '7, 1923 3 Sheets-Sheet 2 Q lll @ew M145 April 11, 1933.

C. H. FOSTER SHOCK ABSORBER 3 Sheets-Sheet 5 Filed June 7, 1929 rlltillllllli Ime/nto@ Patented Apr. l1, 1933 Applieatiorneniea June?, 1929. senai No. seated-*ff i' r1 This invention relates to shock absorbers such as are interposed between the axles and bodies of automobiles for the purpose of checking relative movements'V therebetweenl 5 due to the encountering` of obstacles or Idepressionsby the wheels, and is an improvement of the shock absorberishown inmy copending application, Serial No. 285,910,1:iled June 16,1928. j 10 Y The shock'absorber herein shovvnfconsists generally of a brake drum with" a composite brake` band arranged externally of the drum, and a strap operatively connected to the said band forA operating the same, there being a 35 springconnected with the band fortaking in the slack' 'of' the strap and for moving the brake band therewith, as the vehicle members approach each other. 1 v

'1 It is the general purpose and object ofthe e 29 invention to provide a shock'absorber which is not only `simple of construction and eco:

nomical of production, but will automatical--v ly effect the gripping or braking laction of` the brake band upon the drum by the sep- 25 aration of the body and axle and which also will automatically eii'ect therelease of such gripping or braking action under `conditions to be pointed out hereinafter. further object of the invention is to provide ashock 39 absorber of this `character with means for varyingthe gripping or braking action of the band upon the drum, thereby to adapt' the shoclrabsorber for varying conditions in n service. t

A vstill further object of the invention is to pro-vide a shock absorber of this type which is capable of withstanding and accommodating all ordinary `incidents of use. -Further and more limited objects of the invention G will appear hereinafter andwillrbe realizedY in and through the construction and arrangement ofparts shown in the drawings hereof, wherein Fig.A 1 representsa sectional elevation 'of a shock absorber constructed `in-ac- A i 5 cordance with myxlnvention, showing vthe,

y part-sin the positions which they occupy when the vehicle springs are compressed somewhat more than under ordinary or normal riding conditions; Fig. 2, asectionalview corre'-` 9 spondingfto theline 2 2 of Fig. l; Fig. 3,

a View similar to lFig.,1,"showing the ,parts inthe positions which theyl assume when the. axle and vehicle bodyhave approached each other following a more severe compression of the vehicle springs; Figfll, alview similar to 551 Y Figs.` 1 and 3, showingthe positions'of the parts when the body and axleshall have-sep. arated a suflicient distance Vtofrelease the" braking action; Fig.l 5, ya rear elevation ofthe shock absorber shown in the preceding. views, 6D? with certain parts broken' away; Figs; '.6 and 7V are details in sectional elevation showing the erds of'ltlie'brakje band and thefcooperatingfa justa esto or yar in the ri in actionofthe sadrliand.v *gf g 65M 'Describ'ng the'v various aparts by, reference characters, lfdenotes one ofthe sideframe members and `2v the aXle housing of alveliicle; j S'denotes a cylindrical brake drum, having a? bottom or 'back wall,"thefzce'ntral portion 14: 0 of which isoifset outwardly from fthe periph# V eral Vportion, such offset portion beingseatfed lyvithin a metalv disk `6 .having `a rounded peripheral-flange 6a. The brake drum is sev cured to the sidey frame-,member l bymeans 7-5 of bolts, the shanks ofwhich areindicated-at v 7- and which shanks project throughfopenings in the parts 1, 4g and'. Each bolt is provided with an enlarged cylindrical head l8 withinfthelbody of the brakedrum, the opposite 80" Y ends of the bolts beingthreaded and providedwi'th nuts 9 and lock'washers 10.

The bolt heads 8 areprovided each? with a transverse bore 8aadapted to receive .the in,- n ner end 11a of a helical spring 11, thereby to 85 anchorY the spring within *the drum;l The outer end lllof thesaid spring is secured to thelinner or rear facefofftheflat front or outer 'plate `12 ofthe outerc'over'member of a housing,1which' cover member comprisesl the said plate; and a cylindrical .wall-*124:* `The end 11b may be secured to the plate 12Lin' Vany convenient manner, as. by'meansfoffone or more'inner clamping members 13 having each a V-shaped. groove-at its centerY adaptedto 99' engage the said end ofth'espring, the clamp# ingmembers being rivetedfthrough the plate 12 to a plate lton the front of the plate 12', which" plate 14` may be afname plate. f-

- i TheI wall 123L telescopes over acylindrcal 190 e of dust into the interior of thehous'ing which encloses the brake drum and thebrake band.

The entrance of dust is further prevented'by means of the flanged disk 66f.

The housing constituted by the parts A12,

' 12l and 15, 15'ct is spaced from the brake drum and is movable with reference thereto, for a purpose to vbe explained hereinafter. n

-17 ydenotes a spring `metal band having therewithin and attached to one end thereof a frictionband 18, the said band being of any suitable material, such as fabric belting. Thel spring band 17 is given a curvature such thatit tends to hold the band18 in close engagement with the out'ersurface ofthe drum 3. yThe composite band Ycomprisingthe parts 17 and 18 is of such length that, when vapplied to the`drum,.rits vends willbe spaced apart. It is connected at one end tothe housing wall 15 by means of rivets l19.- The thickness ofthegcompositeband is less than-'the normal width Yofthe space' between the'bralreA band'and` the housing wall 15, so that the end B'of thebrake band which is attached to '-.the housing wall 15,:is lifted clear of Vand spaced from the said drum, as shown particularly in Figs. V1, 2 and 4. lAllof the brake band except the part adjacent'to the rivets 19 is in Vengagement with'the brake drum, due to the curvature ofthe band 17; and the, vend A of -suchicomposite band-which is opposite that connected to-the housing is further pressed into engagement with the brake drum by studs 2O of anti-friction material (such as arguta wood) vwhich aremounted in thewall 15 and engage the outer surface of the band 17. The ends of the; band '17 are flanged toward Vthebrakedrum, asshown at 21, 21a, one end vof thebandlS being inclined and lthe ange 21being inclinedto correspond thereto, as shown in Figs. 1, 4, 6 and 7. Thefopposite end of the band'18 is cutfoii' at right angles to the length-of the said band and the iiange 21a also extends at right-angles to the length-of the band 17. vBecause of thisV construction ofthe 'ends of the composite brake band, the flanges' 21 and21vf*A converge Vfrom the outer or front of the housing toward the rear. In thespace betweenV these flanges a block '22 is slidablyf, mounted, the said block having a'face 222t ,adapted to engage Vtheflange '21a and a tapered face'22badaptedt`o engage the flange 2.1. This'block ismounted forad- Justment in the space between theV ends of the vbrake band upon a screw bolt 23 which is is conveniently secured to both walls 12@L and 15 of the housing by means of short screw' bolts 25'extending through a metal plate 26 on the outer surface of the strap and through a curved metal plate 27 welded to thehousing wall12a and through the said wall and the wall 15. The lower portion of the strap C is looped around the axle housing 2, and the extreme end 24:a -of such portion is fastened tothe body of the strap by means of a U-bolt 28,.plates 29, and nuts 30 on the ends yof the legs of the bolt. v

In'Figs. 1 and 2, the parts A and B are shown as somewhat above the positions which y they occupy during ordinary .or normal riding. Owing to the fact that the housing floats withr reference tothe brake -drum,qsome light pressure'will be exertedsthroughthe strap C and the end B of the brake band Vupon the Y drum. The opposite end B of the strap will be 'fr-ee. fromthe drum, as explained hereinbefore. :It will be. noted that, when kin the position shown inFigsl ,and 2, the brake' Y band can travel in a clockwise direction .only a short distance before .thestrap C will be; substantially tangent to Y theA surface of .the part of the housing immediately over suchl .built-upend. The purpose of this arrange-v ment will be explained hereinafter.'

With the parts yconstructed and arranged'k as described, when the wheels encounter an obstacle which moves the axle toward the body, the spring 11 will move the brake bandl freely in a counter-clockwise direction around the brake drum, taking in the slack of the strap C. No ,matter how rapid may be the movement'of the axle toward the body', or vice versa,`the spring is under suficient torsion to enable it immediately to move the brake band around the drum and to take in the slack of the strap. At the end of this movement, Athe parts may beapproximately in the positions shown in Fig. 3, with the .block22 engagingv the liange 21"L with one side thereof but having its beveled side spaced from the flange 21. Onv rebound, or 4separation of the body and axle, the strapv C, due tothe floating of the 'iousing to which itis connected as well as to` the somewhat yieldingy nature ofvzthe ,houSr ing, willpress the end A of thebrake band against the drum, while pulling on the opposite end of the strap,l against such pressure. vThis pressing of the end'A o-f the brake band will be accomplishedthrough the antil friction studs 20, which will permit the housing to slide over said studs', while holding the end A in engagement withlthe brake drum.

Irrespective of the Vposition of the block'22,

the more severe Vor rapidlth'e rebound of the vehicle' body, the more quickly and stronglyl will the brake band lact upon'the drum, with the result that the rebound or separation will be resistedin proportion to such violence of action or rapidity of separation.;l The ad-f justable block 22 permits, however, of a variation in the amount of braking resistance to such rebound movements. A

However, it is not desirable' that the braking action shall continue throughout the yentire range of rebound movement, 'as "this would interfere with ease of riding and with the desirable action vof the vehiclelsprings. Therefore,.as the end A of thebrake band approaches a position where'the strap (listan-l gent to the housing,` the pressure of suchend A of the band upon the brake Adrum is r e' laXed and, when this position of tangencfy is reached and the said end shall have passed beyond the pointrwhere it can be pressed against the drum bythe strap C, further sepa- Vration will be resistedf onlyfby the vehicle springs and by thecomparativelyf slight re# sistance afforded by thespringllV-andthe then light grip of thebrake band.` 1

1 An 'important' further 'advantage ofl-the construction and arrangement'of partsshown herein is that, when riding under normal conditions, if one-or `moreof the wheels' ofthe vehicle should drop into a holein the road,

there will bepractically nobraking action, as the end A of the brake `band is so-located that it is not pressed against the brakedrum by the brake band and passes below the point where such actioncan occur. This prevents the body fromibeing pulled Vdown by the axle, to the discomfort 'ofthe' occupants of the'vehicle. l Y, VFurthermore, becauseA of the factthat the housing isV movable or iioats with reference to the brake drum and because ofthe fact that the metal of which it is composed isresilient; the end lA of the brake band will als ways be in effective engagement with the brake drum and the housing when the ybody and axle aremoving away from each otherup to the point where the end A shall have passed below theplace at which it is subjected to the pressure of the strap C.

In describing the invention, it has been assumed, for convenience of description, that the vbrake drum and housing will be carried by one ofthe sideframe members `and ,that

the strap@ will "be vsecuredtofthe,upperpor-` f tion kof i the housing and .extend arouiids'uch upper portion, with its low'er lend secured 7o Y to the aXle housing-,and the termsupper' andlower? have been used in connection 'with such descriptiombut without anynten'tion Y of limitingk thereby the use of the inventionl to such speciiicflocation andarrangement of parts'. v: l. l j; Furthermore, while` I have described: the

flexible memberV C asa straplQI dolgnotiner. Y tend thereby to limit my invention as to the use of'any, particular material orto anylpar -ticular shape of `material which may be employed for such Vstrap orlmemben f 'l The .spring 11: is normally'underzflightv compression, as well' asunder'torsion, whereby itv ,presses the packing l16 against:l the back wall 'pof' the brake drum,- 'thereby com# pensating for wear and vpreventing, entrance of dust, etc.,into the housing.y Y Y I claim is:

" LA shock absorber comprising .an innerV brake drum, la housing Vsurrounding:fand'- spaced from said drum andradially' mov-f able with respect to the saiddrlimy a* brake bandV interposed between the. housing 'land thedrum, the said band comprising :aninner Vfriction bandt and an outer springmetalband,

7 Havingthus describ d myinvention, what Y l one end'of the-1j Vspringmetalf.:band pressing thefa'dj acent end ofthe' friction 'band against the drum,"means'connecting theuoppositeiend of the friction band andfspringf `band tothe housing,there being af'space normally. provided between such* attached `endsofLthef saidl bands and thebrake `d rum,`a 'strap ,con-` nectedto the said housingfa spring connected y interposed', between the housing and 5 the drum,'means connectingoneendof the band to theV housing, there ,being a-spaceznormally 1 providedbetweenrsuch'attached end oflthe4 said band andthe brake drumga strap'con.-

nected tofthesaid housing, a" spri'ngsconnected to the housing and tending `t"`oresist` 120 turning of thehousingbythe'strap, andantifrictionf means `interposed,between the housfV l ingand .the free end ofthe brake band L 3. A shock absorber comprising an'vlnner brake. drum, ahhousingisurroundingland spa-ced from f said drum* andi-radially ,move

ablelwith respect .tothe saiddrumpalbrake band A interposed between the.` .housing'vand the drum, .the said band' comprising -anjinner friction band and an outer spring metal band',

oneend cf thespringcmetalfbandlpressin'g thee adjacent end of the friction -band against theV drum, ymeans connectingthe opposite end of thefriction band and spring vband t0 the housing, vtherefbeinga space normally provided betweensuch attached ends ofthe said bands and-*thebrake drum, a strap connected to the saidzhousing,a spring connected to the housing and tending tovfresist rotation of the housing by the strap, and a plurality of anti-friction vstuds mounted in the hous-z ing and arranged A.to engage the free end portionof 1the spring metal band.v *l v 4.A shock Vabsorber comprising` an inner brake drum,` a vhousing surrounding and spaced from .saiddrum and radially mov? able with respectv to. the-said drum, a brake band interposed between the housing and the drum, the said band comprising an inner frictionf'band and an outer spring metal band, voneend of the spring metal band pressing the adjacent end'of the friction band against the drum,cmeans connecting the opposite end.v of'thefriction band and spring 4'band to the housing, there being'a space normally providedbetween such attached ends of fthe saidbands landthe brake drum, a

-strapconne'cted vtoithe said housing, a. spring connected .to the housing and tending to resistmotation of the housing `by the' strap, aY plurality off anti-friction studs mounted `in-fthe,housing and arranged to fengage the free'y end portion of the 'spring Lmetal band,

' and meansfor varying'the eXtent-of movement of ithe attached end of lthe brake V band toward/the unattachedend thereof.'`

A'shock absorberV comprising anrinner ment by the strap, and means for varying the extent of movement ofthe attachedendA 1 of the band toward the unattached end thereof, thereby'to'vary the frictional resistance opposedlby such Vband tothe turning movement ofthe housing. t f r j 6*.' A shock, absorber 'f comprising an linner brake drum,V aV housing surrounding the said band upon the drum, thereby to vary the frie tional resistance opposed by such band to the turning movement of thehousing. A

v 7. A shock absorber comprising an inner brake drum, a housing surrounding the said drum and radially movable with respect K thereto, a brake band interposed between .the housing and the drum and having one end in engagement with ,the drum and its opposite end connected to the housing and nor,

mally spaced. from the drum, the ends of the said .band being spaced and one of such ends beinginclined, afblocly interposed between the ends of the brake bandy vand adjustable alongfthe space provided therebetween, the

said block'having an inclined face adapted.

to cooperate with the inclined ,end of the band, a strap secured to the housing'forturning the latter with respect to the drum, a spring connected to the housing for resist-k ing such turning movement by the strap, and means for varying the amount of'movement of the' attached end of the band toward the unattached end thereof, thereby to vary the Y l y l frictional resistance opposed by suchvban'd to the turning movement of the housing.

8. A shock .absorber comprising an inner-v brake drum, ahousing'surrounding the said drum Jand radially Vmovable with respect thereto, acomposite band interposed between the housing and thedrum, the said bandcomprising an inner friction band and an outer. spring metal band, the :spring bandbeing provided'With end flanges constituting l,the

Y ends of the composite'band, oneV of such end vflanges being inclinedywith a space between such flanges, one of the 'ends o fY saidcomposite band beingrin engagement with the drum andthe other end being connected to v the-housing and normally spaced. from the drum, av bloclrinterposed between the ends of the brake band and vadjustable along the space provided therebetween, the said block f having an inclined face adapted tocooperate with the linclined iiange ofthe band', a strap secured to the housing fory turning the latter with respect tothe drum, andlral spring connected to the housingy for resisting such turning movement by thestrap. d A A In testimony whereof, I hereunto aiixmy signature. Y 'CLAUD FOSTER.:

drumfand radially `movablel with respect i I thereto, a lbrake band interposed between the housing :and the brake' drum, means connect- Y inglone end` of kthe band tof the khousing,la strapA securedV .to the housing for turning the latteriwith respect to the drum, a spring connectedto the housing for vresisting vsuch turning Imovement pbyxthev strap, and means'l for Varying the;V gripping f actionr of Vthe brake 

